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1.
Abstract. A key to the eggs of the equid stomach bot flies is presented. Scanning electron photomicrographs of eggs are used to illustrate differences among the eight Gasterophilus species. The eggs include those of G.haemorrhoidalis (Linnaeus, 1758), G.inermis (Brauer, 1858), G.intestinalis (De Geer, 1776), G.meridionalis (Piller and Evans, 1926), G.nasalis (Linnaeus, 1758), G.nigricornis (Loew, 1863), G.pecorum (Fabricius, 1794), and G.ternicinctus Gedoelst, 1912. The eggs of G.meridionalis and G.ternicinctus are shown for the first time. Egg profile is the same for a particular species and is used as a key character for egg identification. Colour of eggs is used in some couplets but only as a supplemental character. Absence or presence of striae on the eggs is used as a primary contrasting character to separate G.pecorum from the other seven species. Shape of the striae varies on eggs of the same species, even those dissected from the same specimen, and is therefore deemed an unreliable taxonomic character for further separation of the Gasterophilus species. Eggs of the same species taken from specimens throughout the world appear the same in profile. Two sets of eggs require close inspection for adequate identification: G.inermis and G.nigricornis separated primarily by the shape of the microphylar region; and G.intestinalis and G.ternicinctus separated by the shape of the egg ventrum. All other eggs have very unique and distinctive profiles. Only G.pecorum was found to possess the Type-II egg attachment organ (AO) used for adherence of the egg to plants or flat surfaces. The eggs of the remaining seven species possess a Type-I AO used to attach the eggs to hair shafts. The type of AO and the degree that the Type-I AO is extended posteriorly were used as key characters in the first and second couplet respectively.  相似文献   

2.
张科  张钰  王臣  葛炎  初红军  张彦豹  张东  李凯 《生态学报》2023,43(14):5840-5849
黑腹胃蝇是新疆荒漠草原优势种马胃蝇,对放归至当地普氏野马构成了严重威胁。该蝇将卵产在牧草上并以此感染采食者——马科动物,其幼虫于宿主消化道营寄生生活,至三龄老熟幼虫随宿主粪便进入环境化蛹,成为当年新的疫源。于黑腹胃蝇幼虫两个发生峰期(4—5月和8月)对普氏野马核心区新鲜粪便和黑腹胃蝇幼虫点位进行了调查,采用最小凸多边形法(MCP)和固定核域法(FKE)计算粪便分布范围,并通过核密度分析(KDE)辨识幼虫聚集区域和特征。结果表明:(1)在黑腹胃蝇种群第一、第二峰期,野马采食草场拥有最多的胃蝇幼虫采集占比(57.25%、41.94%),其次是驴道、山坡、水源地区域;(2)最小凸多边形法(95%利用率)和固定核域法(95%利用率、0.006带宽值)均能较好估算野马粪便分布范围,第一峰期普氏野马粪便范围(60—70 km2)稍大于第二峰期(50—60 km2)。在所调查的八个水源地,两个发生高峰期均包含红柳、5号、6号3个水源地,并形成了以水源地为重要支撑点、依托毗邻草场交叉传播的连续、非均匀疫源地分布特点;(3)水源地附近草场具有更高的黑腹胃蝇幼虫...  相似文献   

3.

Background  

Chlamydia pecorum is an obligate intracellular bacterium and the causative agent of reproductive and ocular disease in several animal hosts including koalas, sheep, cattle and goats. C. pecorum strains detected in koalas are genetically diverse, raising interesting questions about the origin and transmission of this species within koala hosts. While the ompA gene remains the most widely-used target in C. pecorum typing studies, it is generally recognised that surface protein encoding genes are not suited for phylogenetic analysis and it is becoming increasingly apparent that the ompA gene locus is not congruent with the phylogeny of the C. pecorum genome. Using the recently sequenced C. pecorum genome sequence (E58), we analysed 10 genes, including ompA, to evaluate the use of ompA as a molecular marker in the study of koala C. pecorum genetic diversity.  相似文献   

4.
云雾算盘子(Glochidion nubigenum Hook. f.)于1988年被描述为中国分布新记录种,但同时所引证的凭证标本(李渤生、程树志4533;采于西藏墨脱)实际属于米什米算盘子(G. mishmiense Hook. f.),而《中国植物志》及Flora of China等分类学著作中关于云雾算盘子的形态特征描述与上述凭证标本及云雾算盘子原始形态描述均不符,因此前人关于云雾算盘子在中国的分布记录属于标本鉴定错误所致。近期在西藏日喀则市亚东县的野外考察中发现了真正的云雾算盘子野生居群,证实中国确实有该种分布,故对该种在中国的地理分布区信息予以修正,并提供了该种详细的形态特征描述与野外活体图片。  相似文献   

5.

Background

Chlamydia pecorum is an important pathogen of domesticated livestock including sheep, cattle and pigs. This pathogen is also a key factor in the decline of the koala in Australia. We sequenced the genomes of three koala C. pecorum strains, isolated from the urogenital tracts and conjunctiva of diseased koalas. The genome of the C. pecorum VR629 (IPA) strain, isolated from a sheep with polyarthritis, was also sequenced.

Results

Comparisons of the draft C. pecorum genomes against the complete genomes of livestock C. pecorum isolates revealed that these strains have a conserved gene content and order, sharing a nucleotide sequence similarity > 98%. Single nucleotide polymorphisms (SNPs) appear to be key factors in understanding the adaptive process. Two regions of the chromosome were found to be accumulating a large number of SNPs within the koala strains. These regions include the Chlamydia plasticity zone, which contains two cytotoxin genes (toxA and toxB), and a 77 kbp region that codes for putative type III effector proteins. In one koala strain (MC/MarsBar), the toxB gene was truncated by a premature stop codon but is full-length in IPTaLE and DBDeUG. Another five pseudogenes were also identified, two unique to the urogenital strains C. pecorum MC/MarsBar and C. pecorum DBDeUG, respectively, while three were unique to the koala C. pecorum conjunctival isolate IPTaLE. An examination of the distribution of these pseudogenes in C. pecorum strains from a variety of koala populations, alongside a number of sheep and cattle C. pecorum positive samples from Australian livestock, confirmed the presence of four predicted pseudogenes in koala C. pecorum clinical samples. Consistent with our genomics analyses, none of these pseudogenes were observed in the livestock C. pecorum samples examined. Interestingly, three SNPs resulting in pseudogenes identified in the IPTaLE isolate were not found in any other C. pecorum strain analysed, raising questions over the origin of these point mutations.

Conclusions

The genomic data revealed that variation between C. pecorum strains were mainly due to the accumulation of SNPs, some of which cause gene inactivation. The identification of these genetic differences will provide the basis for further studies to understand the biology and evolution of this important animal pathogen.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-667) contains supplementary material, which is available to authorized users.  相似文献   

6.
白毛算盘子(叶下珠科)在中国无分布   总被引:1,自引:0,他引:1  
张文华  郭永杰  李玉玲  姚纲 《广西植物》2022,42(10):1645-1651
长期以来,白毛算盘子(Glochidion arborescens Blume)被认为广布于中国云南西部至南部地区。该研究基于多年野外考察及标本查阅工作发现,由于白毛算盘子在中国的分布实为标本错误鉴定所致,相关错误鉴定的标本绝大部分属于绒毛算盘子[G.heyneanum(Wight&Arn.) Wight],少部分属于里白算盘子(G.acuminatum var.acuminatum Müll. Arg.)、毛果算盘子(G.eriocarpum Champ. ex Benth.)、艾胶算盘子[G.lancolarium(Roxb.) Voigt]或厚叶算盘子[G.zeylanicum var.tomentosum(Dalzell) Trimen]等物种,故在此将白毛算盘子在中国的分布予以排除。另外,对白毛算盘子进行了后选模式指定,并提供了白毛算盘子与相关混淆种的物种检索表。  相似文献   

7.

Background  

Chlamydiosis and Q fever, two zoonosis, are important causes of ruminants' abortion around the world. They are caused respectively by strictly intracellular and Gram negative bacterium Chlamydophila abortus (Cp. abortus) and Coxiella burnetii (C. burnetii). Chlamydophila pecorum (Cp. pecorum) is commonly isolated from the digestive tract of clinically inconspicuous ruminants but the abortive and zoonotic impact of this bacterium is still unknown because Cp. pecorum is rarely suspected in abortion cases of small ruminants. We have developed a multiplex PCR (m-PCR) for rapid simultaneous differential detection of Cp. abortus, Cp. pecorum and C. burnetii in clinical samples taken from infected animals.  相似文献   

8.
Diseases associated with Chlamydia pecorum infection are a major cause of decline in koala populations in Australia. While koalas in care can generally be treated, a vaccine is considered the only option to effectively reduce the threat of infection and disease at the population level. In the current study, we vaccinated 30 free-ranging koalas with a prototype Chlamydia pecorum vaccine consisting of a recombinant chlamydial MOMP adjuvanted with an immune stimulating complex. An additional cohort of 30 animals did not receive any vaccine and acted as comparison controls. Animals accepted into this study were either uninfected (Chlamydia PCR negative) at time of initial vaccination, or infected (C. pecorum positive) at either urogenital (UGT) and/or ocular sites (Oc), but with no clinical signs of chlamydial disease. All koalas were vaccinated / sampled and then re-released into their natural habitat before re-capturing and re-sampling at 6 and 12 months. All vaccinated koalas produced a strong immune response to the vaccine, as indicated by high titres of specific plasma antibodies. The incidence of new infections in vaccinated koalas over the 12-month period post-vaccination was slightly less than koalas in the control group, however, this was not statistically significant. Importantly though, the vaccine was able to significantly reduce the infectious load in animals that were Chlamydia positive at the time of vaccination. This effect was evident at both the Oc and UGT sites and was stronger at 6 months than at 12 months post-vaccination. Finally, the vaccine was also able to reduce the number of animals that progressed to disease during the 12-month period. While the sample sizes were small (statistically speaking), results were nonetheless striking. This study highlights the potential for successful development of a Chlamydia vaccine for koalas in a wild setting.  相似文献   

9.
Klug, C., Schweigert, G., Fuchs, D. & Dietl, G. 2009: First record of a belemnite preserved with beaks, arms and ink sac from the Nusplingen Lithographic Limestone (Kimmeridgian, SW Germany). Lethaia, 10.1111/j.1502‐3931.2009.00203.x A recent discovery of an unusually preserved belemnite from Nusplingen comprises the extraordinarily rare remains of beaks and nearly in situ arm hooks, as well as the ink sac and an incomplete phragmocone. So far, Hibolithes semisulcatus ( Münster, 1830 ) is the only belemnite known from the Nusplingen Lithographic Limestone (Upper Jurassic, Late Kimmeridgian, Beckeri Zone, Ulmense Subzone; SW Germany) that has the same phragmocone shape and size, and thus we assign the new specimen to this taxon. The rostrum was probably lost due to a lethal predation attempt in which the prey was killed but not entirely eaten. For the first time a specimen reveals details of the belemnite beak morphology, which we compare with the beaks of other Jurassic coleoids. This specimen presently represents the only known rostrum‐bearing belemnite of post‐Toarcian age with preserved non‐mineralized body parts. With the new discovery, Nusplingen now represents the only locality which has yielded complete beak apparatuses from all major Jurassic cephalopod groups. □Beaks, Belemnitida, Coleoidea, Germany, Late Jurassic, morphology, taphonomy.  相似文献   

10.
The mating system of the coreid bug, Colpula lativentris, was studied, and compared with those in other hemipteran bugs. Copulating pairs formed a compact aggregation on a shoot of the Japanese knotweed, Polygonum cuspidatum, and there continued copulation and feeding for more than one day. This aggregation was defined as “a shoot aggregation”. Other than this aggregation composed of copulating pairs, there were loose aggregations on the ground composed of males and females not in copula. This loose aggregation was defined as “a ground aggregation”. Males searched for receptive females mostly in a ground aggregation. Sex ratio was constant and variance of sex ratio was also very small in any shoot aggregations and in large ground aggregations. However, in small ground aggregations, sex ratio was strongly male biased and variance of sex ratio was fairly large. This was because receptive females tended to leave a small ground aggregation and join a large one. These results suggest that a male can attain higher mating success in a larger ground aggregation.  相似文献   

11.
In the red algal genus Gloiopeltis, five species (G. complanata, G. dura, G. frutex, G. furcata and G. tenax) are currently recognized, but genetic analyses have suggested considerably greater species diversity. Gloiopeltis specimens formed nine highly supported clades, six of which are morphologically referable to G. furcata. In order to identify the clade corresponding to true G. furcata, we examined the morphology and genetics of the type specimen of Dumontia furcata Postels & Ruprecht, the basionym of G. furcata, housed in the Herbarium of V.L. Komarov Botanical Institute (LE). A clade comprising the type and specimens from the northwestern to northeastern Pacific Ocean was determined to correspond G. furcata. We concluded that the type locality of G. furcata is Sitka, Alaska, based on the identity of haplotypes. We investigated the genetic divergence of populations within this species, using specimens covering most of its distributional range. We confirmed the merger of G. minuta and G. dura with G. furcata.  相似文献   

12.
Summary

Recently, a specimen of Glossogobius callidus was collected in the Marico Oog, a major source of the Limpopo River in the western Transvaal. This locality is some 1500 km from the river mouth. Earlier taxonomic confusion of Glossogobius giuris and G. callidus has resulted in the omission of G. callidus from identification keys published before 1979. As a result, that species has not been recorded from the Limpopo system. A previously published record of G. giuris from that system, at a locality about 950 km from the sea, is now shown to be based on a misidentification of G. callidus specimens.  相似文献   

13.
14.
15.
A specimen of the rare squid genus Octopoteuthis (Cephalopoda: Octopoteuthidae) from 1600 m in the Sardinian Channel (central western Mediterranean) is described. Meristic and morphological data are provided. The specimen was a spent female and details of the reproductive system and implanted spermatangia are reported. Genetic analysis of this specimen and comparison with those available for species in this genus were carried out. Due to issues associated with the taxonomy of the genus Octopoteuthis, it was not possible to identify the specimen to the species level. The taxonomy of the genus is discussed.  相似文献   

16.
Partial 16S nucleotide sequences of Chlamydia psittaci isolates S26/3 (abortion), P94/1 (pigeon) and Chlamydia pecorum isolates W73 (enteric) and E58 (encephalomyelitis) were determined. Analysis of these data indicates very high levels of interspecies sequence conservation, with C. psittaci being more closely related to C. pecorum than to C. pneumoniae or C. trachomatis. Restriction enzyme analysis of nucleotide sequences indicated that BslI can be used to clearly distinguish C. psittaci and C. pecorum isolates. Psittacine and non-psittacine (pigeon) avian isolates of C. psittaci were distinguished using MaeI.  相似文献   

17.
Relative weight (Wr) is an important and commonly used condition index that provides a measure of the well‐being of a fish population by comparing the actual weight of a specimen with the ideal weight of a specimen of the same species and of the same length in good physiological condition, i.e. the standard weight (Ws). Two methods of calculating the standard weight are proposed in the literature: the RLP method and the EmP method. The aim of this study was to develop a standard weight equation for European perch by means of both methods, using length–weight data from 64 913 fish from 18 countries (across Europe and Oceania). The resulting equations were: log10 (Ws) = ?3.1483 + 1.2663 log10 (TL) + 0.4291 [log10 (TL)]2 for the EmP method and log10 (Ws) = ?5.3493 + 3.2152 log10 (TL) for the RLP method. The applicable length‐range of the two Ws equations was restricted to 80–460 mm. A further research aim was to compare the performances of RLP and EmP. The resulting quadratic EmP Ws equation did not exhibit length‐related biases, which suggests that it can be used to compute relative weight for European perch.  相似文献   

18.
An illustrated key is provided to the 19 genera of the subfamily Idolothripinae from China, and a checklist given to 62 named species, of which six species are newly recorded from China, together with the genus Bolothrips that is represented by two un-named species. A generic diagnosis is given for each genus, along with some discussion of systematic relationship problems and species diversity. Identification keys to species of 11 genera are provided, and Megathrips antennatus Guo, Feng & Duan is considered as a new synonymof Megathrips lativentris (Heeger).  相似文献   

19.
Conformational preferences of the modified nucleosides N2-methylguanosine (m2G) and N2, N2-dimethylguanosine (m22G) have been studied theoretically by using quantum chemical perturbative configuration interaction with localized orbitals (PCILO) method. Automated complete geometry optimization using semiempirical quantum chemical RM1, along with ab initio molecular orbital Hartree–Fock (HF-SCF), and density functional theory (DFT) calculations has also been made to compare the salient features. Single-point energy calculation studies have been made on various models of m2G26:C/A/U44 and m22G26:C/A/U44. The glycosyl torsion angle prefers “syn” (χ = 286°) conformation for m2G and m22G molecules. These conformations are stabilized by N(3)–HC2′ and N(3)–HC3′ by replacing weak interaction between O5′–HC(8). The N2-methyl substituent of (m2G26) prefers “proximal” or s-trans conformation. It may also prefer “distal” or s-cis conformation that allows base pairing with A/U44 instead of C at the hinge region. Thus, N2-methyl group of m2G may have energetically two stable s-trans m2G:C/A/U or s-cis m2G:A/U rotamers. This could be because of free rotations around C–N bond. Similarly, N2, N2-dimethyl substituent of (m22G) prefers “distal” conformation that may allow base pairing with A/U instead of C at 44th position. Such orientations of m2G and m22G could play an important role in base-stacking interactions at the hinge region of tRNA during protein biosynthesis process.  相似文献   

20.
PCR amplification of a region of the large subunit ribosomal DNA sequence with Glomus specific primers was used to detect arbuscular mycorrhizal fungi in root tissue of four plant species. The primers were specific to Glomus mosseae, Glomus caledonium, Glomus geosporum, Glomus coronatum, Glomus fragilistratum and Glomus constrictum, and did not recognise sequences from Glomus claroideum. Sequence differences between isolates were detected by Single Stranded Conformation Polymorphisms (SSCPs) in polyacrylamide gels under non-denaturing conditions. Isolates of G. mosseae, G. caledonium and G. coronatum could be separated by their SSCP patterns, while three isolates of G. geosporumshowed no variation. Specific SSCP patterns from isolates of G. mosseae and G. caledonium allowed detection of both fungi in the same root segment. Sequence differences leading to variations in SSCP patterns were confirmed by direct sequencing. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

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